Limiting fabric standards
Contents |
[edit] Introduction
The building regulations require that reasonable provision be made to limit heat gains and losses through the fabric of new buildings and works to existing buildings. The approved documents to the buildings regulations set out the limiting standards for the properties of the fabric elements of the building.
[edit] L1A, new dwellings, 2013 edition
Roof | 0.2 W/(m^2K) |
Wall | 0.3 W/(m^2K) |
Floor | 0.25 W/(m^2K) |
Party wall | 0.2 W/(m^2K) |
Swimming pool basin | 0.25 W/(m^2K) |
Windows, roof windows, glazed roof-lights, curtain walling and pedestrian doors | 2.0 W/(m^2K) |
Air permeability | 10.0 m^3/(h.m^2) at 50 Pa |
[edit] L2A, new buildings other than dwellings, 2013 edition
Roof | 0.25 W/(m^2K) |
Wall | 0.35 W/(m^2K) |
Floor | 0.25 W/(m^2K) |
Swimming pool basin | 0.25 W/(m^2K) |
Windows, roof windows, roof-lights, curtain walling and pedestrian doors | 2.2 W/(m^2K) |
Vehicle access and similar large doors | 1.5 W/(m^2K) |
High-usage entrance doors | 3.5 W/(m^2K) |
Roof ventilators (inc. smoke vents) | 3.5 W/(m^2K) |
Air permeability | 10.0 m^3/(h.m^2) at 50 Pa |
[edit] L1B and L2B, existing dwellings and existing buildings other than dwellings, 2010 editions
New thermal elements | Retained thermal elements | |
Wall | 0.28 W/(m^2K) | |
Pitched roof – insulation at ceiling level | 0.16 W/(m^2K) | 0.16 W/(m^2K) |
Pitched roof – insulation at rafter level | 0.18 W/(m^2K) | 0.18 W/(m^2K) |
Flat roof or roof with integral insulation | 0.18 W/(m^2K) | 0.18 W/(m^2K) |
Floors | 0.22 W/(m^2K) | 0.25 W/(m^2K) |
Swimming Pool basin | 0.25 W/(m^2K) | |
Wall – cavity insulation | 0.55 W/(m^2K) | |
Wall – external or internal insulation | 0.30 W/(m^2K) |
NB Approved Document C gives limiting values for individual elements to minimise the risk of condensation.
[edit] Related articles on Designing Buildings Wiki
- 2013 changes to the approved documents for part L of the building regulations
- Approved documents.
- Building Regulations.
- PA ratio.
- Part L.
- U-value.
[edit] External references
- Approved Document L1A: Conservation of fuel and power in new dwellings, 2013 edition.
- Approved Document L2A: Conservation of fuel and power in new buildings other than dwellings, 2013 edition.
Featured articles and news
ECA Industry Awards 2024 shortlist revealed
22 leading businesses from across the electrotechnical and engineering services sector.
Government unveils Skills England strategy
Skills England to transform opportunities and drive growth.
New Government Hub for York Given Planning Green Light
For up to 2,600 civil servants, due for completion by 2028.
Construction Skills Certification Scheme cards
July update on Professionally Qualified and Academically Qualified Person Cards.
BSRIA Briefing 2024, November 22
Sustainable Futures: Redefining Retrofit for Net Zero Living.
The CLC on driving competency in the retrofit sector
Previously published roadmap on skills for net zero.
The first labour government King's speech in fifteen years
Construction industry reactions, support and some concern.
CIOB Retrofit of Buildings Technical Information Sheet
What retrofit is, the approach to be taken and processes to be followed.
Adapting Historic Buildings for Energy and Carbon Efficiency
Historic England advice note 18, free download published.
10 retrofit projects revisited 10 years after completion.
Information orders, building liability orders and SPVs
Key BSA terms and how they impact special purpose vehicles.
Listed despite problems with its design.
Zen and the art of cycling exploration.
Design Council Homes Taskforce launched
To support government 1.5 million homes target within UK climate commitments.